This invention relates to a document positioning device for printing apparatus, and more particularly to such a device utilizing photoelectric means for selecting and controlling the lines on the document to be printed.
In an application Ser. No. 433,096 filed Jan. 14, 1974 now U.S. Pat. No. 3,912,068 (continuation of Ser. No. 249,856 filed May 3, 1972, now abandoned) entitled "Printer Having Document Thickness Compensation Device," by O. Kwan, J. J. Boyce and W. A. Ottersen, which is assigned to the assignee of the present invention, there is described printing apparatus which may be used in a bank teller terminal for performing printing operations on a document such as a bank passbook. The document is inserted in a document holder in the printing apparatus and the teller or operator either manually moves the holder with the document positioned therein to the desired printing position or by key operation actuates a document holder transport means to move the document into the desired print position. In order to operate the document holder automatically, an accurate step pulse count is required to accurately position the mechanism using a stepping motor. Furthermore, loss of power, system noise, etc. could cause the stepping motor to misstep, thereby mispositioning the document. Then, too, in automatic operation there is no assurance or confirmation that the positioning to a selected line has been achieved.
Accordingly, it is an object of this invention to provide a new and improved document positioning device for a positioning of a document in a printing apparatus which is simple and accurate.
Another object of this invention is to provide a novel document positioning device which is relatively immune from dispositioning due to system noise and does not require an accurate step pulse count.
A further object of this invention is to provide a new and novel document positioning device which has both a coarse and vernier position control to insure accurate positioning for each line on a document which is to be printed.
Another object of this invention is to provide a novel document positioning means which can be operated in response to information recorded on the document and read by the printing apparatus.
A still further object of this invention is to provide a document positioning means which can be positioned manually while providing an electrical detent action on such operation.